Queries not generating GROUP BY clause with static annotation crashes on SQLite

[Simon Legtenborg]

Django ORM is not generating a GROUP BY clause with static annotation.
After filtering, Django ORM inserts a HAVING clause, but GROUP BY is missing.

Expected Behavior
The Django ORM should generate a SQL query with a GROUP_BY clause when using .values() and .annotate() methods on a queryset.

Actual Behvaior
The ORM is not generating a GROUP BY clause when a static annotation is used. However, it does generate it when a non-trivial annotation is used.

Steps to reproduce

With a small model

class Book(models.Model):
    title = models.CharField(max_length=100)
    pages = models.IntegerField(default=0)

and the corresponding view

def bug_view(request):
    queryset = Book.objects.all()
    print(f"query: {queryset.query}")

    # trivial annotation
    annotated_queryset = queryset.annotate(group=Value('all'))
    print(f"annotated_query: {annotated_queryset.query}")

    # grouped_and_annotated_query won't have a GROUP BY clause
    grouped_and_annotated_queryset = 
    annotated_queryset.values('group').annotate(sum=models.Sum('pages'))
    print(f"grouped_and_annotated_query: {grouped_and_annotated_queryset.query}")

    # filtered_query contains HAVING clause but no GROUP BY clause
    filtered_queryset = grouped_and_annotated_queryset.filter(sum__gt=10)
    print(f"filtered_query: {filtered_queryset.query}")
    return HttpResponse(filtered_queryset)

Django raises a django.db.utils.OperationalError. The (printed) querries are

query: SELECT "books_book"."id", "books_book"."title", "books_book"."pages" FROM "books_book"

annotated_query: SELECT "books_book"."id", "books_book"."title", "books_book"."pages", all AS "group" FROM "books_book"

grouped_and_annotated_query: SELECT all AS "group", SUM("books_book"."pages") AS "sum" FROM "books_book"

filtered_query: SELECT all AS "group", SUM("books_book"."pages") AS "sum" FROM "books_book" HAVING SUM("books_book"."pages") > 10

As you can see, there is no GROUP BY keyword in the grouped_and_annotated_query. But after filtering, a HAVING keyword is inserted, without a GROUP BY. This is the main reason for this error. This happens only to static annotations. If i evaluate a more complex annotation, the grouping works as intended:

def without_bug_view(request):
    queryset = Book.objects.all()
    print(f"query: {queryset.query}")

    # non-trivial annotation
    annotated_queryset = queryset.annotate(large=Case(
        When(pages__gt=650, then=Value(True)),
        default=Value(False),
        output_field=BooleanField()))
    print(f"annotated_query: {annotated_queryset.query}")
    grouped_and_annotated_queryset = annotated_queryset.values('large').annotate(sum=models.Sum('pages'))
    print(f"grouped_and_annotated_query: {grouped_and_annotated_queryset.query}")
    filtered_queryset = grouped_and_annotated_queryset.filter(sum__gt=0)
    print(f"filtered_query: {filtered_queryset.query}")
    return HttpResponse(filtered_queryset)

querries:

query: SELECT "books_book"."id", "books_book"."title", "books_book"."pages" FROM "books_book"

annotated_query: SELECT "books_book"."id", "books_book"."title", "books_book"."pages", CASE WHEN "books_book"."pages" > 650 THEN True ELSE False END AS "large" FROM "books_book"

grouped_and_annotated_query: SELECT CASE WHEN "books_book"."pages" > 650 THEN True ELSE False END AS "large", SUM("books_book"."pages") AS "sum" FROM "books_book" GROUP BY 1

filtered_query: SELECT CASE WHEN "books_book"."pages" > 650 THEN True ELSE False END AS "large", SUM("books_book"."pages") AS "sum" FROM "books_book" GROUP BY 1 HAVING SUM("books_book"."pages") > 0

The GROUP BY keyword is inserted as is should.

Here is the Stack Trace for completeness:

Error
Traceback (most recent call last):
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 89, in _execute
    return self.cursor.execute(sql, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/backends/sqlite3/base.py", line 328, in execute
    return super().execute(query, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
sqlite3.OperationalError: a GROUP BY clause is required before HAVING

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/books/tests.py", line 8, in test_bug_view
    response = client.get("/books/bug")
               ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/test/client.py", line 927, in get
    response = super().get(path, data=data, secure=secure, headers=headers, **extra)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/test/client.py", line 457, in get
    return self.generic(
           ^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/test/client.py", line 609, in generic
    return self.request(**r)
           ^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/test/client.py", line 891, in request
    self.check_exception(response)
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/test/client.py", line 738, in check_exception
    raise exc_value
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/core/handlers/exception.py", line 55, in inner
    response = get_response(request)
               ^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/core/handlers/base.py", line 197, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/books/views.py", line 23, in bug_view
    return HttpResponse(filtered_queryset)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/http/response.py", line 376, in __init__
    self.content = content
    ^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/http/response.py", line 401, in content
    content = b"".join(self.make_bytes(chunk) for chunk in value)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/models/query.py", line 398, in __iter__
    self._fetch_all()
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/models/query.py", line 1881, in _fetch_all
    self._result_cache = list(self._iterable_class(self))
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/models/query.py", line 208, in __iter__
    for row in compiler.results_iter(
               ^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/models/sql/compiler.py", line 1513, in results_iter
    results = self.execute_sql(
              ^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/models/sql/compiler.py", line 1562, in execute_sql
    cursor.execute(sql, params)
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 80, in _execute_with_wrappers
    return executor(sql, params, many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 84, in _execute
    with self.db.wrap_database_errors:
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/utils.py", line 91, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 89, in _execute
    return self.cursor.execute(sql, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/simonlegtenborg/PycharmProjects/djangoProject/venv/lib/python3.11/site-packages/django/db/backends/sqlite3/base.py", line 328, in execute
    return super().execute(query, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
django.db.utils.OperationalError: a GROUP BY clause is required before HAVING

[David Sanders]

Thanks for the report 👍

[David Sanders]

This appears to only affect SQLite.

I haven't tested on Oracle.

[David Sanders]

Jacob & Simon discovered this is only for SQLite < 3.39.0 which allowed a HAVING clause without a GROUP BY: ​https://www.sqlite.org/releaselog/3_39_0.html

[Mariusz Felisiak <felisiak.mariusz@…>]

In b863c5ff:

Fixed #34967 -- Fixed queryset crash when grouping by constants on SQLite < 3.39.

On SQLite < 3.39, this forces a GROUP BY clause with a HAVING clause
when no grouping is specified.

Co-authored-by: Simon Charette <charette.s@…>